Crankcase vapor recycling system



March 22, 1966 w. M. KENNEDY 3,241,534

CRANKCASE VAPOR RECYCLING SYSTEM Filed Aug. 23, 1965 IN VEN TOR.

ATTORNEY United States Patent 3,241,534 CRANKCASE VAPOR RECYCLING SYSTEM Wallace M. Kennedy, Bloomfield Hills, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Aug. 23, 1963, Ser. No. 304,056 4-Claims. (Cl. 123-119) This invention relates to crankcase vapor recycling systems, and more particularly to an improved crankcase vapor recycling system located internally of the engine.

It is known to recycle crankcase vapors into the cylinders of internal combustion engines by providing external piping and Valving for communicating the crankcase with the inlet manifold of the engine. This invention provides an improved crankcase vapor recycling system located internally of the engine to thereby eliminate all external piping and valving.

An object of this invention is to provide an improved crankcase vapor recycling system.

Another object of this invention is to provide a crankcase vapor recycling system including means communicating the crankcase with at least one cylinder fluid inlet passage and located internally of the engine to convey the crankcase vapors to one or more cylinders for combust-ion.

A further object of this invention is to provide a crankcase vapor recycling system including mean communicating the crankcase with at least one cylinder fluid inlet passage comprising at least one opening in an internal engine wall separating a valve mechanism chamber from a cylinder fluid inlet passage in order to convey the crankcase vapors to one or more cylinders for combustion.

Still another object of this invention is to provide a crankcase vapor recycling system including means communicating the crankcase with at leat one cylinder fluid inlet passage comprising flow control means located in at least one opening in an internal engine wall separating a valve mechanism chamber from a cylinder fluid inlet passage in order to convey a controlled flow of crankcase vapors to a cylinder for combustion.

Yet a further object of this invention is to provide a crankcase vapor recycling system including means communicating a valve mechanism chamber of the engine with a pair of adjacent cylinder fluid inlet passages and extending through both the wall separating the valve mechanism chamber from the fluid inlet passages and through the partition separating the fluid inlet passages in order to convey crankcase vapors to a pair of cylinders for combustion through a single means.

Further objects and advantages of the invention will be apparent from the following specification and drawings, wherein:

FIGURE 1 is a cross-sectional view of a V-type internal combustion engine embodying a crankcase vapor recycling system according to this invention;

FIGURE 2 is an enlarged sectional view taken generally along the plane indicated by line 22 of FIGURE 1;

FIGURE 3 is a fragmentary cross-sectional view of a portion of the cylinder head showing another embodiment of the invention; and

FIGURE 4 is a sectional view taken generally along the plane indicated by the line 44 of FIGURE 3.

Referring now to the drawings, an engine includes a cylinder block 12 and a crankshaft 14 rotatably mounted in an enclosed crankcase portion 16 of the cylinder block 12 and connected by connecting rods 18 to pistons 20 which are located within cylinders 22 of the cylinder block 12. Cylinder heads 24 close the upper ends of the cylinders 22 and include inlet passages 26 which respectively communicate each cylinder with an inlet manifold 28 for carrying combustible fluid mixtures from a car- 3,241,534 Patented Mar. 22, 1966 buretor 30 mounted on manifold 28 to the cylinders. Rocker covers 32 are mounted on the cylinder heads and define therewith chambers 34 containing valve actuating mechanisms 36. Cylinder heads 24 further include wall means 38 separating inlet passages 26 from the valve mechanism chambers 34.

In normal operation of the engine crankcase vapors, such as blow-by gases and lubricating oil vapors, are present in the engine crankcase 16 and are carried into the valve mechanism chambers 34 through connecting passages 40. For descriptive purposes the crankcase 16, valve mechanism chambers 34 and connecting passages 40 may be thought of as comprising a single compartment 42 in which crankcase vapors are present. The crankcase 16 is provided with an air inlet device, not shown, for admitting ventilating air to scavenge the crankcase vapors collecting therein. Reference may be made to Schrader 2,991,775 for a showing of such a device.

In order to provide for the recycling of crankcase vapors into one or more of the engine cylinders the present invention provides communicating means 44 extending through wall means 38 and joining the valve mechanism chambers 34 with the fluid inlet passages 26. The result is the formation of a fluid flow system from the crankcase 16 adjoining the lower end of cylinders 22 through passages 40, valve mechanism chambers 34, communicating means 44 and fluid inlet passages 26 to the cylinders 22. It should be understood that any number of communicating means 44 may be provided, each joining a valve mechanism chamber with one or more inlet passages, depending on the construction of the engine. It is not necessary that all inlet passages be connected with a valve mechanism chamber.

Communicating means 44, as shown in FIGURE 2, includes a threaded opening 46 in wall 38 having flow control means such as a valve 48 threadably engaged therein. The valve comprises a cylindrical body 50 having a spring biased orificed member 52 reciprocably mounted therein. Crankcase vapor entering valve 48 from chamber 34 pass through axial bore 54, around the flange shaped end of member 52 through transverse bore 56, orifice 58, axial bore 60, and into inlet passage 26. Alternatively, crankcase vapors may pass around the conically shaped end portion of member 52 bypassing transverse bore 56 and orifice 58. Movement of the conically shaped end of member 52 against the bias of the spring in response to the flow of crankcase vapors is effective to reduce the flow area of the internal passage and thus provide automatic restriction of excessive scavenging fluid.

The embodiment of this invention shown in FIGURES 3 and 4 differs from that previously described in that opening 46 in wall 38 connects with an opening 62 in a partition 64, separating two adjoining fluid inlet passages 26 and 26 so that valve mechanism chamber 34 is connected with two fluid inlet passages by a single means.

In summary, the invention provides an improved crankcase vapor recycling system having internal means for communicating the crankcase with one or more cylinder fluid inlet passages and controlling the flow of crankcase vapors therethrough.

What is claimed is:

1. In an internal combustion engine having a pair of cylinders, a compartment within the engine communicating with one of the ends of said cylinders, a pair of passage means communicating with the other ends of said cylinders, including a separating partition and having a common wall with said compartment, the improvement comprising means located internally of said engine, communicating said compartment with said pair of passage means through said common wall and said partition.

2. The combination of claim 1 wherein said communicating means includes flow control means to control the flow of fluids through said communicating means.

3. In combination With an internal combustion engine having at least one cylinder, a crankcase within the engine communicating with one end of said cylinder, a cylinder head closing the other end of said cylinder, passage means through said cylinder head and communieating with said cylinder other end, removable cover means on said cylinder head and defining therewith a valve mechanism chamber, Wall means in said cylinder head and separating said passage means from said valve mechanism chamber and means communicating said crankcase with said valve mechanism chamber, the improvement comprising opening means through said Wall means and communicating said valve mechanism chamher with said passage means to recirculate crankcase avpors into the engine cylinder and a flow control valve retained in said opening means and removable from said valve chamber side of said Wall means.

4. In combination with an internal combustion engine having a pair of cylinders, a crankcase Within the engine communicating with one end of each of said cylinders, a cylinder head closing the other ends of said cylinders, removable cover means on said cylinder head and defining therewith a valve mechanism chamber, means communicating said crankcase with said valve mechanism chamber, and a pair of passages through said cylinder head and each communicating With one of said cylinders other ends, said passages being separated by a partition and having a common Wall With said valve mechanism chamber, the improvement comprising opening means through said common Wall and said partition and communicating said valve mechanism chamber With said pair of passages to recirculate crankcase vapors into both said cylinders and a flow control valve retained in said opening means and removable from said valve chamber side of said Wall means.

References Cited by the Examiner UNITED STATES PATENTS 2,120,050 6/1938 Lowther 123-1 19 2,547,587 4/1951 Lowther.

2,906,252 9/1959 Beardsley 1231 19 2,991,775 7/1961 Schrader 123-1l9 MARK NEWMAN, Primary Examiner.

FRED E. ENGELTHALER, Examiner. 

1. IN AN INTERNAL COMBUSTION ENGINE HAVING A PAIR OF CYLINDERS, A COMPARTMENT WITHIN THE ENGINE COMMUNICATING WITH ONE OF THE ENDS OF SAID CYLINDERS, A PAIR OF PASSAGE MEANS COMMUNICATING WITH THE OTHER ENDS OF SAID CYLINDERS, INCLUDING A SEPARATING PARTITION AND HAVING A COMMON WALL WITH SAID COMPARTMENT, THE IMPROVEMENT COMPRISING MEANS LOCATED INTERNALLY OF SAID ENGINE, COMMUNICATING SAID COMPARTMENT WITH SAID PAIR OF PASSAGE MEANS THROUGH SAID COMMON WALL AND SAID PARTITION. 